Quran 22:39 Al-Hajj, ayah 39 of 78

أُذِنَ لِلَّذِينَ يُقَـٰتَلُونَ بِأَنَّهُمْ ظُلِمُوا۟ ۚ وَإِنَّ ٱللَّهَ عَلَىٰ نَصْرِهِمْ لَقَدِيرٌ ۝٣٩

22:39 Sanction is given unto those who fight because they have been wronged; and Allah is indeed Able to give them victory;